Lyocell fiber with recycled cellulose

ABSTRACT

The invention relates to a Lyocell fiber with recycled cellulose, which uses recycled cellulose pulp to dissolve in the spinning solution. The weight percentage of the recycled cellulose in the spinning solution is 30% to 55%. The Lyocell fibers of the invention also have hydrophilic, cooling, drape, antistatic, and biodegradable properties compared to the Lyocell fibers without recycled cellulose.

FIELD

The present invention relates to a Lyocell fiber, especially Lyocell fiber using recycled cellulose as raw material.

BACKGROUND

The manufacturing process of Lyocell fiber includes steps of pulping, dissolving, spinning, and washing. That is, wood pulp is usually dissolved in N-Methylmorpholine-N-Oxide (NMMO) solvent, and the raw silk is obtained after the spinning step. The raw silk is washed with water to remove the NMMO solvent remaining to make a cellulose fiber finished product.

Natural fiber finished products can be classified according to staple and filament, but their manufacturing processes are still different. The manufacturing process of staple includes cutting, compressing, blending, spinning, and other processing procedures. Staple has lower requirements of non-breaking and uniform shaping. The filament manufacturing process requires unlimited stretching of the fiber, and hence characteristic of the prepared yarn is not liable to break and be made in one-step. The concentration of long-chain cellulose molecules in the used spinning solution is usually higher. The viscosity of the spinning solution is relatively increased, and the yarn does not tend to break during the process. Staple finished product has rough and hairy appearance while filament finished product has brighter, smooth appearance and robust texture. Therefore, staple and filament apply to different textiles.

Due to the rising awareness of environmental protection in recent years, the green environment and sustainable development have attracted much attention. Governments of various countries are vying to strive for long-term goals of environmental protection and sustainable development. The private people are also committing to developing “green products,” making products harmless or hardly harmful to the environment during the acquisition of raw materials, manufacture, sales, use, and even disposal. Such products are conducive to renew or recycle and reuse resources and help achieve low pollution, recyclability, and resource-saving. Clothes re-made from second-hand clothes or sportswear made from recycled PET bottles are examples of “green products.”

Whether natural fiber or artificial fiber products, both cause varying degrees of pollution to the environment in a series of textile processes such as drawing, spinning, weaving, printing, dyeing, and subsequent processing. Thus, the related industries have begun to recycle textiles or use recycled materials to make textiles for the sake of environmental sustainability and resource-saving. For example, there is a known way to obtain natural plant cellulose from recycled clothing materials. The recycled clothing materials are first crushed, the non-fiber components and fiber components are separated, and then the obtained cellulose fibers are used to produce silk threads, textiles, and so forth.

Several methods for reusing recycled fiber materials; however, the silk threads or textiles manufactured on these methods have unsatisfied biodegradable, hydrophilic, cooling, and drape features. Such methods are mainly applied to staple products and not suitable for manufacturing filament ones.

SUMMARY

The main purpose of the present invention is to use higher proportions of recycled fiber materials as raw materials to manufacture Lyocell fiber that also has biodegradable, hydrophilic, cooling, drape, and antistatic properties.

To achieve the above purpose, the present invention provides a Lyocell fiber with recycled cellulose, which uses recycled cellulose pulp to dissolve in the spinning solution comprising 30% to 55% weight percentage of the recycled cellulose in the spinning solution.

The followings are beneficial effects of the present invention. 1. The Lyocell fiber of the present invention can be applied to filament manufacturing; 2. Compared with Lyocell fibers without recycled cellulose, the Lyocell fiber of the present invention also has hydrophilic, cooling, drape, and antistatic, and biodegradable properties. 3. The Lyocell fiber of the present invention is made from a higher proportion of recycled materials, which can help realize environmental protection goals and sustainable development of low pollution, recyclability, and resource-saving.

BRIEF DESCRIPTION OF THE DRAWINGS

N/A

DETAILED DESCRIPTION

General fibers can be divided into natural fibers and artificial fibers. Natural fibers exist in nature. According to different sources, natural fibers can be divided into plant fibers, animal fibers, and mineral fibers. In contrast, artificial fibers refer to fibers made by processing, which can be processed from natural raw materials (for example, Modal fiber, Lyocell fiber, etc.) and can also be synthesized through chemical methods (for example, polyester fiber, nylon, etc.).

The source recycled fiber materials can be recycled natural fibers and recycled artificial fibers. Recycled natural fibers can be processed recycled cotton, recycled wood pulp, recycled paper pulp, recycled hemp (such as recycled flax, recycled ramie, recycled jute), and other recycled natural fibers that contain natural plant fibers. The source of these natural plant fibers can be wholly or partly from clothing manufacturing residues and/or old clothing, wood pulp, rag pulp, textiles, clothing, cotton in order to save resources and achieve the purpose of recycling and reusing fiber materials.

Lyocell fiber is a kind of artificial fiber. The manufacturing method of Lyocell fiber usually follows the steps below. (1) Raw wood pulp fibers are dissolved in N-Methylmorpholine-N-Oxide (NMMO) solvent and are made into cellulose slurry. (2) The spinning solution is discharged through the Filmtruder. (3) After spinning, washing, drying, and other procedures, silk threads are wounded. (4) Finally, the yarn is woven into cloth and then further processed into products for use in clothing, furniture, medical equipment, etc., and sold on the market.

Due to the rising awareness of environmental protection, the green environment and sustainable development issues have received continuous attention. Traditional Lyocell fiber products still require a large amount of natural raw materials, which are prone to resource consumption. Therefore, the present invention provides a Lyocell fiber with recycled cellulose, which can be mainly derived from second-hand textiles, such as recycled clothes, furniture, or other waste textiles to acquire recycled fiber materials and use the recycled fiber materials to make recycled cellulose slurry to obtain recycled cellulose.

The Lyocell fiber with recycled cellulose provided by the present invention can use the Lyocell fiber manufacturing process to mix raw wood pulp and recycled cellulose pulp and dissolve them in NMMO solvent to prepare a spinning solution. The filament spinning process is used for spinning. Besides, the used recycled cellulose pulp can be purified and removed from impurities to improve spinning stability.

The Lyocell fiber with recycled cellulose of the present invention uses 30% to 55% by weight of the recycled cellulose pulp in the spinning solution. Its properties are similar to or better than the silk threads made from raw wood pulp solely. A preferred embodiment of the present invention is 35% to 55% of the recycled cellulose pulp based on the mass of the solution is used in the spinning solution. A more preferred embodiment of the present invention is 43% to 52% of the recycled cellulose pulp based on the mass of the solution is used in the spinning solution. The concentration of the long-chain cellulose molecules in the used spinning solution can be higher so that the viscosity of the spinning solution is increased, and it is able to avoid the breakage of silk threads during the spinning process.

In summary, the present invention has the following beneficial effects. 1. The Lyocell fiber of the present invention can be applied to the manufacturing process of filament; 2. Compared with Lyocell fibers without recycled cellulose, the Lyocell fiber of the present invention also has hydrophilic, cooling, drape, and antistatic, and biodegradable properties. 3. The Lyocell fiber of the present invention is made from a higher proportion of recycled materials, which can help realize environmental protection goals and sustainable development of low pollution, recyclability, and resource-saving.

The description above is merely preferred embodiments of the present invention, and it does not limit the scope of patent protection; therefore, modifications of equivalent effects based on the present specification should be deemed to be included in the scope of the present invention. 

1. A Lyocell fiber with recycled cellulose, which uses recycled cellulose pulp to dissolve in the spinning solution, comprising 30% to 55% weight percentage of recycled cellulose in the spinning solution.
 2. The Lyocell fiber with recycled cellulose of claim 1, wherein the weight percentage of the recycled cellulose in the spinning solution is 35% to 55%.
 3. The Lyocell fiber with recycled cellulose of claim 1, wherein the weight percentage of the recycled cellulose in the spinning solution is 43% to 52%.
 4. The Lyocell fiber with recycled cellulose of claim 1, wherein the recycled cellulose is natural plant cellulose. 